I have a MacBook Pro (17-inch, Mid 2010) Snow Leopard 10.6.8 with 4 GB of ram. I have 220.77 GB of space left on my HD. When I booted my computer up, after the grey screen with the apple logo, a rainbow screen that looked like this came up. The rainbow screen eventually went away and turned into a blue screen, but wasn't booting even after 5 minutes or so, so I did a hard shutdown. I tried booting again, and waited longer, still no luck. Then I booted in safe mode and inserted a Snow Leopard install disk to run disk repair during the next boot. After that, it took awhile to boot up, but did so successfully. Booted fine after that for a couple days, then the rainbow screen came up again. I did a hard shut down and then it booted up fine. As far as the beach ball hiccups, it happens in all programs randomly, for about 5 to 10 seconds. I've tried: Looking at the Activity Monitor, nothing seems to be using up a huge amount of CPU (same programs I used worked fine before my mac suddenly slowed down). Uninstalling chrome (COMPLETELY) and used firefox, made no difference, so I uninstalled firefox (COMPLETELY) and installed chrome again. I disabled the flash that comes with Chrome as well. (which can cause problems apparently with the flash already on the system) Running an extended hardware check (no problems found) Resetting the NVRAM and PRAM Resetting the SMC Running Disk Repair Repairing Disk Permissions Having no login items Cleaning up my desktop I ran OnyX (cleans up all caches) I have the latest system updates I have the latest version of Flash The only thing that happened before I noticed my mac slowing down was: I woke my computer when it was running very low on battery power, it woke instantly. Usually the screen takes a second to come back from being asleep on low battery power, so I thought it was unusual. Did I interrupt it from going into a deeper sleep cycle and glitch something out?